Process of electric welding.



L. Memup .PROCESS 0F ELECTRIC WELDING. APILIUATIOI FILED IAB. 24, 1905.

Patented -Nv. .24, 190s.

Inventor:

LAURENCE Si ncHmn/v Attyy' less of electric welding,

LAURENCE s. LAonMAN,

OF NEW YORK, N. Y., lASSIGNOR T0 STANDARD PULLEY ltIANUFAG'IURING COMPANY, A CRPQRATION OF NEW YORK.

rnoonss or ELECTRIC Mamme.

To all whom it may concern.'

Be it known that I, LAURENCE S. LACH- MAN, a citizen of the United States, and resident of the borough of Manhattan, city, county, and State or New York, have invented certain new and useful Improvements in Processes of Electric lVelding, of which the following is a specification. l

The invention relates to an improvedprocfor welding two sheets of metal together. v

The invention may be a plied to the construction ofpulleys, whees, sheaves, pulley frames and other structures, whereby the parts of the structures may be securely united to each other by an autogenous union without the use of rivets, bolts,

While I have specified certain named devices to which the invention relates, and to which 4the process is particularly applicable,

I amnevertheless not to be understood Vas limitinthis invention to such devices, be-v cause t e process may be used in any connection to which it is'applicable.

Further objects of the invention will hereinafter appear, and to these ends the invention consists of the process of electric weldg "bodging the stepsl as hereinafter fully in for carrying out the above objects, einscri ed and as' c aimed in this specification. Suitable apparatus for carrying out the process is. illustrated -iii the accompanying drawings, in which l re l is a vertical sectional view of a Fi suita le die or press and the parts of a sheet metal wheel or pulle which are to beweldand 6 are insideface views ofy wheel ed together electrical inside aceviews of tV or pulley to'be welded together. .Fig. 4 is a vertical sectional view of the parts of the pulley arranged in juxtaposition. Figs. l5. or u FigsnQ and 3 are e parts of the wheel lley parts 'which may ,be welded toget er.

Fig. 7 is a vertical sectional view of 'said parts placed in juxtaposition. Figs. 8 and 9 are inside face views of coperating portions be welded together.

saine placedone a ainst the other. Figs. 1 1 and 12 are inside ace views of the coperating parts of a pulley, to be welded to ether. Fig. 13 is an enlarged detail sectiona view of the portion of the pulley shown in Fig. 2.'

Fig. 14. is a'vertical sectional view of the Specicato'n of Letters latent. Application and nach 24, i905. sei-in No. 251,712.

com plete keys, and

Patented Nov. 2d, 1908.

pulley after the parts have/been wel ed together. Figs. 15 and 16 are inside face views of co erating portions of a.

' the two sheet metal portions referred to form the parts of a pulley or wheel, the different parts Iof a frame, or tool, or utensil, or other sheet metal structure.

In the drawin s I have illustrated the process as applied to welding together the two coperating portions of a sheet metal wheel or pulley, althou h other devices might have been shown to lustrate the process. Each half of the pulley is provided with a llanged'portion A and body portion B of any desired form, which may be pressed out of sheet metal.`

In welding the two portions of the wheel together in any of the forms illustrated in the drawings, isolated points of contact projecting out of the general plane or surface of the 'metal and each having a much larger area ,of such surface adjacent thereto, are provided between the portions of the wheel, and the metal at the projecting points of contact is welded to ether. In uniting metal bodies provided with protuberances, it is necessary that the welding current employed,

thereby reducing ythe heat generated by the current below a welding temperature.

In Figs. 2, 3 and 4, each half of the wheel is provided with injections() which may be formed in any v.esired manner, as for 'instance, by being forced or pressed from the body portion B. i These projections C may also .be formed by cuts or slits, or pieces of metal punched from the body portion. One portion of the metal is laid upon the other portion as illustrated 'in Fig. 1, with the projections C in contact with each athen-.that is to say, the projections C of one portion of the wheel bear directly upon the projections i C of the otheriportion of the wheel. Gr` reption of which ,is hollowe at H to receive one half Yof the wheel. The punch I is also hollowed out at J to receive the upper half vof the wheel, but the outer portions of the dievand punch are adapted to bear upon the portions of the body of the wheel directly in the rear of the flanges A and over the pro- I jections C.

By way of illustration, the die and punch are shown with diagrammatic electric circuits connected to a suitable source of supply or generator K having a controlling switch L. The parts of the wheel are first laid on the die H andthen the unch I is brought fdown, whereupon the eectric circuit will be completed as soon as the punch comes in contact with the upper half of the wheel. The circuit is completed through the projections C on the arts of the wheel which are in contact wit each other, and with a current of the proper strength, the projections C will be brought to awelding condition at their contacting terminals. The pressure of the punch I 4is continuously applied'as the projections C soften, thereby forcing the two parts of the wheel together and as soon as the welding is complete and have coalesced to form intethe current is switched olf, development of weldin heat having `ceased with the meeting an contacting of the larger areas of metal. adjacent to such projections as the projections Hatten, down. Suitable contacts may be rovided on the parts of the press, which will automatically complete an electric circuit for breaking the circuit at the switch L at the proper time, as for example when the plane faces of the plates meet.

As shown in Fig. 13, the projections C are preferably provided with attened oints 0 in order that projections of one ha f of the wheel may better bear upon the projections of the other half.

In Figs. 5, 6 and 7 elongated peripheral the projections gral, spot welds,

projections P are provided u on one half of the wheel, while elongated ra ial projections Q, are provided upon the other half of the i wheel, and these peripheral and radial projections I? and Q, are arranged so that when one portion of the wheel is arranged opposite the other, the projections Q will cross the projections P, as indicated in Fig. 7 so that there will be intersecting points of contact between the projections. on the two halves of the wheel. When the current is passed through the two portions of the wheel, heat is concentrated at the points of contact between the projections P and Q and 'a iirni weld is obtained by the coalescence of the softened metal at the points of contact, the ortions of these linear projections beyon the point of intersection upon such i ing temperature coalescence coming into contact with the plane faces of the opposing wheel portion and oHering a greater ath for the passag of the current so that evelopmentof wel ceases. 9, one portion of the wheel is provided with a circular ridge or projecting flange R, while the other portion is provided with radial projections S which are adapted to cross the circular ridge R when the two .parts lof the wheel are laid together and thus form points of contact, as illustrated in Fig. 10.`

In Figs. 11 and' 19., the portions of the wheel are provided with elongated ridges or projecting such manner as to cross each other' when the parts of the wheel are laid op osite each other, thereby forming points o contact.

In Figs. 15 and 16, each portion of the wheel is provided with curved ridges or projections U, which coperate to form points of contact, the ridges of one portion of the In Figs. 8 and wheel crossing those of the other portion o f the wheel when the two parts are laid together. i Y

The object in all of the' constructions shown and described is to obtain small points of contact between projecting por-. tions on each partl of the wheel or other sheet metal part to be welded. By this means the heat is concentrated on the projecting portions of the sheet metal parts, thereby producingl a series of isolated autogenous spot welds. g v

I claim and desire `jto obtain" by `Letters Patent the followinfrrj" 1. The process oiP producing lautogenons spot welds which consists in providing metal bodies with a plurality of spaced'r and isolated integral protuberances rising from and above the surfaces to vbe united, placing such bodies with said protuberances in end-to-end contact, and passing a welding current through the engaging protuberances while simultaneously pressing the bodies together until each pan' of protuberanees coalesce to forni an autogenous spot Weld between such bodies and such surfaces meet and contact thereby affording a larger path for said curpressing the sheets together until eachA pairl of protuberances coalesce to form an isolated portions 'I which coperate in welding current through Ythe enconsists in an area of adjacent metal,

Aeo

kother at a multiplicity of separated and dis upon the surface of eac -ducing t `offer a wider autogenous spot weld between the sheets and larger surfaces of metal` adjacent the point of contact in each body mutually meet and contact, thereby affording a. larger path for said current and reducing the generated heat below awelding temperature.'

3. The rocess substantially as herein described otP electrically welding the flat iinperforate surface of one piece of thinsheet metal to the flat imperforate surface of antinctly isolated points between `such flat' surfaces, which consists in first producing series of projections inte al with the sheets.

sheet,"se arated from each other by areas of'at meta and so spaced that the projections on onel'sheet will :egister with those on the other sheet.,4 and form-cooperating points or surfaces ofcontact rising from and above the lane of the sheet, then placing the flat sur aces of the sheets toget er with the projections onone sheet in end-to-end contact with the projections on the other sheet, and finally passing an electric current through the'sheets and the said projections on both sheets, thereb bringin` the projections to a weldin condition-"fan simultaneously pressing t e surfaces of the two sheets together until the engagingprojections coalesce and sink -down an thel at metal ar'eas meet and contact aiiordin a larger path for the current, rei e generated heat below a welding temgerature, whereby the two sheets become firm y welded to ether face to face by a plurality of isolated spot welds.

4. The process of electric welding which providing each of two metal bodies to be united with an isolated projection having an adjacent area of metal, placing said projections in contact, and passing through said bodies a welding current of strength sufficient to bring the contacting areas ofsaid projections to a weldin temperaturewhiie lnsuiiicient to bring sai adjacent areas to a welding temperature, passage of said current being continued unti the. en aging areas of t e projections coalesce an unlte and correspondmg adjacent metal areas on the two bodies meet and `contact and thereby ath to said current and generation of wel ing heat ceases.

5. The process of electric welding which consists in providing each of two metal bodiesto be unitedl w1t an' isolated projection rising above the general surface of such body and of small cross-section compared to placing such projections in end-to-end contact, passing a welding current of suiiicient strength to raise such projections to a welding temperature while insuicient so to heat such adjacent .specification in the ing witnesses.

metal, and forcing the two bodies together 'surfaces of such bodies isolated protuberances elevated above such surfaces, contacting such protuberances end to end, passing through such bodies a welding currentl ofl sufficient volume to heat such rojections to a weldin condition while insu cient to heat material y a conductor of a cross-section corresponding to such metal surface and pressing said bodies together while continuing the passage of such current until said protubern ances weld and coalesce and such surfaces meet to form said conductor of larger cross-A section.

7. The process of electric welding which' consists in forming upon the bodies to be united isolated protuberances, placing such protuberances in contact, passln through suchbodies a welding currento sutcient volume to heat the oint olf contact to a welding temperature-while insuiicient so to heat adjacent metaland pressing said bodies tosaV gether while continulng the passage of current until the metal'at the point of contact of the two bodies softens and coalesces and adjacent metalof the two bodies Vcomes into contact oifering the urrent a conductor of too large section to be heated to a welding v temperature.

8. The process of electric welding which consists in providin each of two metal bodies to be united, with at least one isolated l projection having an adjacent area of metal,

placing the projections of the two bodies in contactand passing through said bodies a welding current of strength suiiicient to bring .thecontacting areas of said rojections to a welding tem tively larger areas of meta rounding said contacting areas, passage of said current being continued until the enn gaging areas of said rojections coaiesce and unlte andrelatively` arger areas of the two metal bodiesadjacent each point of weld meetl and contact, and offer a wider path to said current, and generation of welding heat ceases.

In testimony whereof I have signed this presence of two subscribv LAURENCE sLAoHMA'N.

Witnesses:

A, L. OBmnN, OLIN A. Fosrnn.

erature While 1nsuiicient to bring to a wel in temperature relaimmediately'sur- 

